Abstract

Nuclear lasing of 3He‐Ar at 2300‐Torr total pressure with a thermal neutron flux of 4.3 × 1016 n/cm2 sec has resulted in a lasing output power of 1012 W. A multiple‐path laser cavity was used with seven passes through the laser medium which was pumped by the 3He(n,p)3H nuclear reaction. The thermal neutron lasing threshold flux was 1 × 1016 n/cm2 sec. At 600‐Torr 3He‐(2%)Ar, the threshold flux was 4.7 × 1015 n/cm2 sec. This represents the highest‐power, largest‐volume nuclear laser to date.